Chapter 18: Air Pollution (Alex)

Question 1

The thin blanket of gases surrounding the Earth

Answer 1

The atmosphere

Question 2

The atmospheres’ two innermost layers

Answer 2

The troposphere and the stratosphere

Question 3

The number of gas molecules per unit of air volume

Answer 3

Density

Question 4

Why does the density vary throughout the atmosphere?

Answer 4

Gravity pulls gas molecules towards the Earth’s surface. Therefore the lower layers of the atmosphere have more gases than the upper layers and are denser.

Question 5

The force per unit area of a column of air

Answer 5

Atmospheric pressure

Question 6

Why are density and atmospheric pressure important?

Answer 6

They play major roles in weather

Question 7

In which atmospheric layer is 75%-80% of the Earth’s air mass found in?

Answer 7

The troposphere which is the layer closest to the Earth

Question 8

How far above the equator does the troposphere extend and how far above the poles?

Answer 8

17 km and 6km

Question 9

What two gases make up 99% of the air?

Answer 9

Nitrogen (78%) and oxygen (21%)

Question 10

Rising and falling air currents, winds, and concentrations of CO2 and other greenhouse gases in the troposphere play a major role in the planet’s short term ________ and long term _______.

Answer 10

Weather and climate

Question 11

What is the average weather in a given area called?

Answer 11

Climate

Question 12

What is the second layer of the atmosphere?

Answer 12

The stratosphere

Question 13

Between what elevations is the stratosphere?

Answer 13

17 km and 48 km

Question 14

In what layer is much of the atmosphere’s small amount of ozone found in what is called the ozone layer, and at what elevations is it found?

Answer 14

The stratosphere and between 17 km and 26 km

Question 15

How is most stratospheric ozone produced?

Answer 15

When some of the oxygen molecules in this layer interact with UV radiation emitted by the sun

Question 16

What percent of the sun’s harmful UV radiation is prevented from reaching Earth’s surface by the ozone layer?

Answer 16

95%

Question 17

What is the presence of chemicals in the atmosphere in concentrations high enough to harm organisms, ecosystems, or human-made materials, or to alter climate called?

Answer 17

Air pollution

Question 18

Almost any chemical in the atmosphere can become a pollutant if?

Answer 18

It occurs in a high enough concentration

Question 19

What are some natural sources of air pollutants?

Answer 19

Wind-blown dust, pollutants from wildfires and volcanic eruptions, and volatile organic chemicals released by some plants.

Question 20

Where do most human inputs of outdoor air pollutants occur?

Answer 20

In industrialized and urban areas where people, cars, and factories are concentrated

Question 21

How are most human-made air pollutants produced?

Answer 21

By the burning of fossil fuels in power plants, industrial facilities, and motor vehicles.

Question 22

Chemicals or substances emitted directly into the air from natural processes and human activities at high enough concentrations to cause harm.

Answer 22

Primary pollutants

Question 23

Pollutants formed by the reactions of primary pollutants.

Answer 23

Secondary pollutants

Question 24

According to the WHO, how many people live in urban areas where outdoor air is unhealthy to breathe?

Answer 24

1.1 billion

Question 25

What is a colorless, odorless, and highly toxic gas that forms during the incomplete combustion of carbon-containing materials?

Answer 25

Carbon monoxide (CO)

Question 26

What are the major sources of carbon monoxide?

Answer 26

Motor vehicle exhaust, burning of fossil fuels and grasslands, smokestacks of fossil fuel-burning power plants and industries, tobacco smoke, and open fires and inefficient stoves used for cooking.

Question 27

What is a colorless, odorless gas that only 93% percent of it in the atmosphere is from its natural cycle?

Answer 27

Carbon dioxide (CO2)

Question 28

What are the major sources of carbon dioxide?

Answer 28

The burning of fossil fuels and the clearing of CO2-absorbing forests and grasslands

Question 29

What is a colorless gas that forms when nitrogen and oxygen gas react under high-combustion temperatures in automobile engines and coal-burning power plants and industries?

Answer 29

Nitric oxide (NO)

Question 30

What component of the nitrogen cycle can also produce NO?

Answer 30

Lightning and certain bacteria in the soil

Question 31

In the air, NO reacts with oxygen to form what reddish-brown gas?

Answer 31

Nitrogen dioxide (NO2)

Question 32

Collectively, NO and NO2 are what?

Answer 32

Nitrogen oxides (NOx)

Question 33

Some of the NO2 reacts with water vapor in the air to form what components of acid deposition?

Answer 33

Nitric acid (HNO3) and nitrate salts (NO3-)

Question 34

Both NO and NO2 play a role in the formation of what mixture of chemicals formed under the influence of sunlight in cities with heavy traffic?

Answer 34

Photochemical smog

Question 35

What is a greenhouse gas emitted from fertilizers and animal wastes, and is produced by the burning of fossil fuels?

Answer 35

Nitrous oxide (N20)

Question 36

What is a colorless gas with an irritating odor with about 1/3 of it in the atmosphere coming from its natural cycle, and where do the other 2/3 come from?

Answer 36

Sulfur dioxide (SO2), human sources, mostly combustion of sulfur-containing coal in power and industrial plants.

Question 37

In the atmosphere, SO2 can be converted to ________, which consist of microscopic suspended droplets of sulfuric acid (H2SO4) and suspended particles of sulfate (SO4^2-) salts that return to the Earth as a component of acid deposition.

Answer 37

Aerosols

Question 38

What is a variety of solid particles and liquid droplets that are small enough and light enough to remain suspended in the air for long periods called?

Answer 38

Suspended particulate matter (SPM)

Question 39

About ___ of SPM in the outdoor air comes from natural sources such as dust, wildfires, and sea salt with the other ___ percent coming from human sources, including coal-burning power and industrial plants, motor vehicles, and road construction.

Answer 39

62%, 38%

Question 40

What is a colorless and highly reactive gas that is a major ingredient of photochemical smog?

Answer 40

Ozone (O3)

Question 41

What problems does excess ozone in the troposphere cause?

Answer 41

Coughing and breathing problems, aggravation of lung and heart diseases, reduce resistance to colds and pneumonia and irritate the eyes, nose, and throat. It can also damage plants, rubber in tires, fabrics, and paints.

Question 42

Why is ozone in the stratosphere good?

Answer 42

It protects us from harmful UV radiation.

Question 43

What are organic compounds that exist as gases in the atmosphere or as gases that evaporate from sources in Earth into the atmosphere called? Some examples are hydrocarbons emitted by the leaves of many plants and methane.

Answer 43

Volatile organics compounds (VOCs)

Question 44

What is industrial smog composed of?

Answer 44

An unhealthy mix of sulfur dioxide, suspended droplets of sulfuric acid, and a variety of suspended solid particles in outside air.